BERLIN and RIDGEFIELD, Conn., April 1, 2011 /PRNewswire/ -- New data presented
today at the 46th Annual Meeting of the European Association for
the Study of the Liver (EASL) demonstrate the antiviral activity of
Boehringer Ingelheim's once-daily oral protease inhibitor, BI
201335, in both treatment-naive and -experienced patients with
chronic genotype-1 (GT1) hepatitis C virus (HCV), the most
challenging genotype of HCV to treat. Results from SILEN-C1
show a sustained viral response (SVR) in 71 to 83 percent of
treatment-naive patients who received BI 201335 once-daily plus the
current standard-of-care (SOC) [pegylated interferon (PegIFN) and
ribavirin (RBV)].

Results from SILEN-C2 show an SVR in 28 to 41 percent of
treatment-experienced patients who received BI 201335 once-daily
plus PegIFN and RBV.

"SILEN-C1 and 2 have shown positive Phase 2 results in a broad
range of HCV patients," said Peter
Piliero, M.D., executive director, Medical Affairs,
Boehringer Ingelheim Pharmaceuticals, Inc. "The current
standard-of-care in HCV is not effective for enough patients.
Protease inhibitors such as BI 201335 represent potential new
options to improve outcomes and the possibility to shorten the
duration of treatment for HCV disease."

"Boehringer Ingelheim is continuing its long heritage in
virology and commitment to develop new medicines for HCV,"
continued Piliero. "BI 201335 is part of BI's growing HCV
portfolio, which is being investigated with the goal of improving
treatment and cure rates for HCV patients. We are excited
that we will commence our Phase 3 trial program with BI 201335 in
the near future, based on the results of these Phase 2
studies."

Patients were given BI 201335 for 24 weeks in combination with
PegIFN/RBV, which was given for 24 or 48 weeks. Patients in the two
BI 201335 240mg QD groups who achieved extended rapid virological
response (eRVR, defined as plasma viral load less than 25 IU/ml at
Week four and undetectable at Weeks 8-20), were re-randomized to
discontinue PegIFN/RBV at Week 24 or continue PegIFN/RBV to Week
48.

Treatment
Outcomes in SILEN-C1 (Treatment-Naive Patients)

Placebo(N=71)

120mgQD/LI(N=69)

240mgQD/LI(N=142)

240mgQD(N=142)

eRVR, %

16

80

78

87

SVR, %

56

71

73

83

Breakthrough*, %

3

6

4

3

Relapse**, %

14

7

11

8

*Rebound on treatment with BI
201335

**Rebound after the end of all
treatment

Overall SVR rates reached 83 percent in the 240mg QD group (plus
current SOC). A three-day lead in with SOC prior to initiation of
BI 201335 was seen to reduce responses by 12 percent and 10 percent
in 120mg QD/LI and 240mg QD/LI patient groups. The LI was
also associated with higher rates of viral breakthrough. Of
the patients in the 240mg QD dose group who achieved extended rapid
viral response (eRVR, defined as plasma viral load less than 25
IU/ml at Week four and Weeks 8-20) and were re-randomized at Week
24, 93 percent achieved SVR with 24 weeks of SOC (PegIFN/RBV)
treatment.

The most frequent dose-dependent adverse events (AEs) in BI
201335 treatment groups were gastrointestinal disorders, rash or
photosensitivity, and jaundice resulting from isolated unconjugated
hyperbilirubinemia. Average alanine aminotransferase (ALT)
improved in all BI 201335 groups compared to placebo, and there was
no excess anemia reported in the study. Across BI 201335
treatment groups, 4 to 12 percent of patients discontinued BI
201335 due to AEs.

The SILEN-C2 study evaluated the virological response and safety
of different doses of BI 201335 in treatment-experienced patients
who did not respond to at least 12 weeks of prior treatment with
PegIFN/RBV. This patient population is particularly difficult to
treat, as patients who have not responded to PegIFN/RBV alone have
low response rates to additional treatments. The trial did not
include patients who relapsed after initial treatment with
PegIFN/RBV.

In each group, patients were given BI 201335 for 24 weeks in
combination with PegIFN/RBV, which was given for 24 or 48
weeks.

Patients in the two BI 201335 QD groups who achieved eRVR were
re-randomized to either stop all treatment at Week 24 or continue
PegIFN/RBV until Week 48.

Treatment
Outcomes in SILEN-C2 (Treatment-Experienced
Patients)

240mgQD/LI(N=142)

240mgQD(N=76)

240mgBID/LI(N=70)

eRVR, %

43

45

47

OverallSVR,
%

28

41

31

Breakthrough*, %

25

28

17

Relapse**, %

25

9

19

*Rebound on treatment with BI
201335

**Rebound after the end of all
assigned treatment

BI 201335 once-daily at 240mg plus SOC provided positive Phase 2
results in this very difficult-to-treat patient population. As is
seen in SILEN-C1, a three-day LI with SOC was associated with
decreased viral response. Phase 3 trials of BI 201335 are in
preparation.

The most frequent dose-dependent AEs in BI 201335 treatment
groups were gastrointestinal disorders, jaundice resulting from
unconjugated hyperbilirubinemia, and mild to moderate rash or
photosensitivity. Serious or severe AEs were reported more
frequently in the BI 201335 240mg BID with LI group.
Discontinuations due to adverse events ranged from 4 percent in the
BI 201335 240mg QD without LI group to 23 percent in the BI 201335
240mg BID with LI group.

HCV is an infectious disease of the liver and is a leading cause
of chronic liver disease and liver transplant. The number of
individuals chronically infected with HCV globally has been
estimated at 170 million, with three to four million new infections
occurring each year. Only about 20-45 percent of patients clear the
virus in the acute phase. Of the remaining chronically infected
patients, 20 percent will develop cirrhosis within a mean of 20
years. The mortality rate after cirrhosis has developed is two to
five percent per year. End-stage liver disease due to HCV infection
currently represents the major cause for liver transplantation in
the Western world.

About Boehringer Ingelheim in Virology

Boehringer Ingelheim has more than 6,900 scientists working in
cross disciplinary teams within our global R&D network in six
large therapeutic areas, including virology. In addition to its
ongoing research program for HCV, Boehringer Ingelheim has a
long-standing history in virology drug development, including
compounds for the treatment of HIV. The company has a well
established research center in Laval,
Canada, dedicated to virology research since the early
1990's, and is committed to developing new therapies for virologic
diseases with a high unmet medical need.

Boehringer Ingelheim in Hepatitis C Virus (HCV)

BI 201335 is an investigational oral HCV NS3/4A protease
inhibitor, discovered from Boehringer Ingelheim's own research and
development, which has completed clinical trials through Phase 2b
(SILEN-C studies). This Phase 2 program supports the investigation
of BI 201335 in Phase 3 trials. Boehringer Ingelheim is also
developing BI 207127, an NS5B RNA-dependent polymerase inhibitor
that has completed Phase 1 clinical trials. Phase 2 trials
evaluating BI 207127 with BI 201335 in interferon-sparing regimens,
both with and without ribavirin, are currently underway.

Boehringer Ingelheim Pharmaceuticals, Inc.

Boehringer Ingelheim Pharmaceuticals, Inc., based in
Ridgefield, CT, is the largest
U.S. subsidiary of Boehringer Ingelheim Corporation (Ridgefield, CT) and a member of the Boehringer
Ingelheim group of companies.

The Boehringer Ingelheim group is one of the world's 20 leading
pharmaceutical companies. Headquartered in Ingelheim, Germany, it operates globally with 142
affiliates in 50 countries and more than 41,500 employees. Since it
was founded in 1885, the family-owned company has been committed to
researching, developing, manufacturing and marketing novel products
of high therapeutic value for human and veterinary medicine.

In 2009, Boehringer Ingelheim posted net sales of U.S.
$17.7 billion (12.7 billion euro) while spending 21 percent of
net sales in its largest business segment, Prescription Medicines,
on research and development.